Art of decolorizing, clarifying, and purifying petroleum oils



Jul 26, 1927. 1 536,938

H. L. KAUFFMAN ET AL AR'IHOF DECOLORIZING, CLARIFYING, AND PURIFYING PETROLEUM OILS Original Filed Nov. 11. 1924 aw). naaf'a'nu 26? VAPOR OUTLET cooume TANK /7 W STEAM LANE- EOLVLIBV yr 314mm 01:

HAROLD L. KAUF'FMAN, IRwm A. CLARK,

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- atfol nu 5 FROM CLAY STORAGE.

FROM 0.

Pa ten ted 26, 1927.

UNITED STATES PATENT ormer. Y

34301.!) LEs'rEa KAUFFMAN AND mwm ARTHUR crank, or. minivan, coLomo,

assrenons, Brussm: assrennnnrs, 'I'O sun nunm.

I A31 01' DEOOLORIZING, GLA BII'TIN G, AN D iURII'YIII G PETBOLEUI OILS.

Application filed November 11, 1924, Serial no. 749,353. Renewed February 25, 192'}.

This invention relates to improvements in the art of decolorizing, clarifying and purifying petroleum oils b the use of untreated or finely divided ays and similar filtering materials containing enough water to form a viscous, cohesive mass sufliciently fluid to be pumped through pipes. A1 though this invention is'not limited to any particular petroleum roductit refers more especially to lubricating oils derived from.

crude oils of the Rocky Mountain'region.

The term clay in this invention is .used in abroad sense to include fullers earths, diatomaceous earths, clays of the kaolin and.

related groups, bentonites and other altered volcanic ashes, tufi's, breccias and pyroclasts, and clay minerals such as halloysite, montmorillonite, pyrophyllite, leucite, etc., and

other filtering materials of similar characteristics. I 4';

The coloring matter of petroleum oils, more particularly lubricatingoils, is due mainly to the presence of substances'of a bituminous or asphaltic nature, as well as to the presence of various complex sulphur and nitrogen compounds. In addition to these substances it also is ver probably due to various colloidal and disso ved impurities such as finely divided and colloidal carbon, complex tarrycompounds of high molecular Wei ht, etc.

' -T 1e removal of substances producing color in -a petroleum oil is generally understood to be dependent upon the'phenomenon known as adsorption.

stance, either solid, liquid or gaseous.

Hence, if a-solid' body is introduced into a solution, a-new surface is created, and if the surface tension of the solution at the surface of contact with the introduced substance 'is so influenced by the dissolved substance Adsorption consists in the removal from a solution a part of the 'vary greatly in color.

that it becomes smaller with the increase in in concentration of the dissolved-substances will take place at the surface of contact. ,If the solution is removed fromthe solid body, the layer'with the hi h concentration ofthe solute remains attach In other words the solid body has adsorbed a portion of the solute, and the solution that remains is now less concentrated than" it was originall This is the most generally accepted p ysical explanation of theadsorption process. 1

However, when a decolorizing agent is in troduced into a petroleum oil there also takes place certain changes in the oil itself that are of a chemical nature, such as polymerization of tarry, asphaltic and bituminous substances, unsaturated hydrocarbons, etc. The adsorbent, therefore, acts also as a'polymerizmg agent. 1

The usual method em loyed in improving the color of petroleum oils, particularly lubricating oils, is to percolate the-=oil through a column of coarse fullers earth, with or without the aid of ressure, thereby removing part of the co oring matter and solid particles in the oil; Heavy oils are some times diluted with gasoline, or other solvent, to facilitate percolation throughthe, clay. A

16-30 mesh clay is usually used on heavy oils while a 30-60 mesh clay is more efiicient on the lighter oils.

The disadvantages of this process lie mainl' in the fact that several days are reuire for the complete utilization, of the c ay," and it is" impossible to get the entirethrough-put 'to a uniform color without blending, since fractions are obtained that- It has long been known in the art that by mixing an oil with a decolorizing agent the process of decolorizing and purifying the oil is accomplished in a much shorter periodof time than by the process of percolation.

' More eflicient results are obtained'in this process by the useof finely divided filtering materialof from 100to 200 mesh, since more adsorptive surface is ofl'ered' to the oil to be treated with the same amount-of clay. The clay. and oil are usually mechanically inter-- .concentration of the latter, then an' increase ed to the solidibody."

mixed, heated to the temperature at which is .reached and the. s out o ay is then sepathe, maximum adsorptive capacityof the clay. I

40. I I exert an advantageous either before or after the mixtureis cooled,

We have discovered by practical experimention on clays that have come under our observation, particularly those clays foundin the Rocky Mountain region, that to be used most effectively they should be commingled :V vnine, chloride which we have used success-; fully and to an economic advantage when tainregion containing form a viscous and cohes ve; mass, in treatwith the oil to be treated, while containing enough moisture'to form a viscous, cohesive mass suificiently 'fluid to be pumped through pipes, and after heating the mixture should be steamed down to a temperature slightly in excess of the temperature of boiling water.

We have also found'that in treating certheoil and clay containing 'suflicientmoisture to form a viscous and cohesivemass.

We do not wish to limit ourselves to any par-' ticular substance or substances, nor the quantity of the same that is to be added to the mixture, because" of difierent substances when intermixed with various oils and filtering materials. However, by way of illustration, we may mention of the Rocky .Mou'nintermixed with clays suflicient' moisture to ing oils derived from'crude oils from this It is tobe understood that the same region.

to'the-use of zinc invention is not chloride but that the use of any material hav-- defined above or which;

ing the characteristics action in the presence of superheated steam'which they would not otherwise have, iswithin the scope of the invention, All such materialsareincluded in scopic channels of the internal the material of adsorbed gases'and water, soluble salts,

the term catalyst claims.

We are not fully aware of all the reasons for the increased efiiciency obtained by treat-- as used in -the appended ingoils witha filtering material containing" sufli'cient' moisture 'toform a viscous and cohesive mass, but we believe that the steam, generated from the moisture in the filterin material when intermixed with the oilan heated, enormously increases the adsorptive surface of thefclay by thereby increasing its efiiciency. Also, as the steam generated from the particles of wet clay passes out of the clay par ticles the oil diiluses into the microscopic channels of the. clay and the maximum ad I the surface has sorptive value of the surface is realized as no opportunity to adsorb or time to permit of condecrease ofthe surface tension,

the varying effects ofio'r'adsorption to take place, l 'of adsorption, displacement and repeated ad- 7 clearing the microj structure of position of petroleum oils,

version o amorphous silica into the less adsorptive crystalline form. Furthermore, we believe that the commingling a filtering material containing moisture increases the surface layer of the oil due to the surface created between the oil and water, or the steam to which it is converted on heating'the mixture, thereby greatly increasing thesurface layer of the oil with a resultant and thus of the .oil with.

further. concentrating the dissolved impurities in the free layer'oi the oil, render ng a larger percenta e of these impurities more susceptible to a sorption. Still further, we believe that steam generated by heatin the' wet clay when mixedwith the oil ai polymerizing the unsaturated, asphaltic and bituminous substances in the oil into larger molecular residues thereby rendering them more susceptible to adsorption by the filter- I ing materialif, I w I V Adsorbed nnpurities cannot be removed by washing but can be removed by displacement by other substances and in equal quantities. This however, is a mass action. It is evident that the impurities of petroleum .oils have a greater aflinity'ior-the adsorptive surfaces of solid substances than do the individual I molecules ofwater making up steam.' However, these impurities once adsorbed can be replaced by hot water or steam when excess due to mass action as shown in recover ing spent cla in this manner; It is that when t ese a haltic and bituminous substances are adsor don the surface of a possible solid particlethey are not only polymerized intolarigei'. molecular, residues but are also lumped together in large particles which when displaced by steam are removable from the oil by subsequent filtration and thesolid particlesj'of the filtering material thus freedoftheads'orbed impurities willagain adsorb more impurities from theoil as they come into contact with the oil again during agita-' I -tion'. I o Thus a continuous cycle is established .which is only by a the ultimate decrease otthe concentration of the'dissolved impurities to a int where the influence of the solid partic es of the adsorbent on the concentration of these dissolved impurities in the surface layer of the oil Such a cycle sorption: could reach th1 ultimate point of is not suflicient low concentra'tiononly under the most ideal the complex comconditions, impossible with but we believe such changes do'take place to; anvextent that greatly increases so treated. V

Further, the adsorption of impurities by articles of the clay may also be-due to the act that in acid solutions, i. e. acid treated the decolorizati'on, of oils oils, asphaltic material is positively charged;

while, in contact with water or steiimfthe adsorbent becomes negatively charged and ing and a may of the clay and be deposited on it.

In general, the action of a catalytic agent isnpt fully understood, but we are of the opinion however that, when used in our process, one or more of the following actions take place: First, that the catalystor cata lyt-ic agent in the presence of steam tends to polymerize more rapidly and completely the unsaturated, asphaltic, tarry, bituminous and similar substances into. forms of higher molecular residues, thereby rendering these materials more susceptib e to adsorption. Secondly, the catalyst in the presence of steam may effect the surface of the adsorbent in such a manner as to increase its influence, on the surface tension of the oil, thereby increasing the concentration of the soluble impurities in the surface-layer of the oil so that when the solution is removed from the solid adsorbent more of the soluble impurities will remain attached to the adsorbent and be removed from the oil.

The preferred process of our. invention is more readily understood by referring to the accompanying drawings which illustrate, diagrammatically, the form of an apparatus by which the preferred process of our inventionmaybemonducte In the drawing 1 re resentsa'line from the Wet clay storage tan to pump 5 through valve 2,---3 represents a line from the acid oil storage tank also leading to pump 5 hlollgh valve 4. Pump 5 discharges into stirrers. The agitator 6 is discharged through valve 7 a and pump 8 to the heating coils 9 which empt into vapor separator 11 through pipe 10. team is admitted to the vapor separator 11 through valve 13 fromsteam -iine 15 and steam and vapor escape from the vapor separator 11 through the vapor outlet 12 into the vapor outlet line 22. The vapor separaior is discharged through valve l i'into cooling tank 16 and from there the oil and claymixture is passed into the filter feed tank through valve 17 pump 18 and pipe 19. 21 represents a p ipelea'ding-from or other mechanical device for separating the spent filtering material from the oil.

With sthe a paratus: in the form shown in the drawing fire process is condu ctechasfol lows:

From the wet clay storage tank and the acid oil storage tank the proper mixture of wet clay, withor without a catalytic agent, and acid oil is drawn into the a. 'tator 6 through valves 2 and 4; respectively y means of ump 5. The wet clay andoil are thoroug ly intermixed in the agitator by means of mechanical or other agitation and then themixture is drawn from the agitator 6 through valve 7 and passed through the heating 0011s by means 0 pump 8 as slowly as is a convement without heating the mixture-to a temperature inexcess of the boiling point of Y the 011 being treated... From the heating coils 9 the mixture passes into the vapor separator 11 through pipe 10 and is steamed down toatemperature somewhat in excess of-the boiling point of water by means of steam admitted into the bottom of the vapor separator 11 through valve 13, the steam and vapors escaping from the separator through outlet 12;

From the vapor separator 11 the partially cooled mixture is discharged into the cooling tank 16, orother suitable cooling device, where the mixture is further cooled to the desired temperature for separating the spent filtering material from the oil; From the cooling tank 16 the cold or semi-cooled mixture is pumped into the filter feed tank 20 through valve 17 and pipe 19 by means of pump 18. From there the mixture of oil and filtering material is. fed to filters, centr'ifuges or other mechanical device for relriipving the spent filtering material from the o What we claim is:

Y L An improved process of decolorizing,

clarifying and purifying petroleum oils which consists in mixing the oil by any 'mixture through a suitable heating device A/ agitator 6 whiElTise'quippedwitlnnechaniealwvithout ea m suitable means with untreated, finely dithe mixtureitwemperature in excess of the boiling point Yif tlTe oil being treated, then steaming down the hot oil and clay mixture to a temperature somewhat in excess of the boiling point of water and drawing oil the vapors with the spent steam, further cooling the mixture to the desired temperature for separating the spent filtering material from the 'oil and separating the spent filtering material from the oil. I

2. An improved process of decolorizin clarifying and purifying etroleum oi s which consists in mixing the oil by any suitable means with untreated finely divided clays containing zinc chloride as a catalytic agent and enough water to form a viscous,

cohesive mass sufiiciently fluid to be pumped through pipes, passing the mixture through a suitable heating device without heating the oil and clay mixture to a temperature inexcess of the boiling .poiifi of the oil being treated, steaming down the hot oil and clay mixture to a temperature somewhat in excess'of the boiling pointofwaterf clays containing weight-of water to clay, passing the" mixture througha suitable heating device without heating the-mixture to a temperature in e ces drawing-off the'vapors with the spen'tsteam, further coo'lino:v temperature for separating the spent fi1te1'- the-spent and further coolin the mixture to the desired temperature @or separating the spent filtering -material from the oil.

3., An improved process of decolorizing, clarifying 'andfpurifying etroleum oils which consists t e oil by any suitable means witlifl untreated finely -divided Emmi-30% to 500% by excess ofthe boiling point of the oil being treated, thensteaming down the hot oil and. clay',mixture to a temperature somewhat in "f the hoiling po'int' 'oiQwater-and the mixture ;to the desired :material ,from the oil and separating filtering material from the. oil

i 4. An improved process of decolorizlng;

' a ent, passin clarifying andpurifying petroleum oils which consists in mixing the oil by any; divided filtering materialscon taining 'from :to 500% of weight of suitable means with untreated finely clays and clay-like water to clay and zinc chloride as a catalytic the mixture through a suita le heating orizing and chloride andthereafter heatin sists of intermixing terial. ,In testimony; .our signatures.

evice without heating the mixture to a temperature in excess ofithehoiling point of the oil being treated, steaming down the hot oil and clay mixture to a temperature somewhat in excess of the boiling point. of water, further cooling the mixture to the desired temperature for separating the spent filtering material from the oil and separating the spent filtering material from the oil. i i 5. The herein described method of decolpurifying petroleum oils which consistsof mixing the'oil to be treated with a viscous mass of finely divided untreated clay and water in the presence of zinc the mixture to a point in excess ofjthe point of water.'

' '6. The; herein described step decolorizing and purifying petroleum oils which conthe oil to 'be. treated with a filtering material consisting of water and finely divided untreated clay n'the proportion of 30% to 500% by weight of water to clay and zinc'chloride as a catalytic mawhereof we afiix HAROLD! LESTER 'KAIl'FFMAN. IRWIN earner: CLARK. 

